Motor assembly for boats



June 1967 R. G. LAUGHLIN 3,32

MOTOR ASSEMBLY FOR BOATS Filed May 18, 1965 2 Sheets-Sheet 1 I x II II II II I II I] II II INVENTOR. RAUL G. LAUGH LIN ATTORNEYS June 13, 1967 R. ca. LAUGHLIN 3,324,821'

MOTOR ASSEMBLY FOR BOATS Filed May 18, 1965 2 Sheets-Sheet 2 INVENTOR. RAUL G. LAUGHLIN 2564022 z Wal a/21a A TTORNE YS United States Patent 3,324,821 MOTOR ASSEMBLY FOR BOATS Raul G. Laughlin, 2325 Wilshire Blvd., Santa Monica, Calif. 90403 Filed May 18, 1965, Ser. No. 456,742 5 Claims. (Cl. 115-34) This invention relates generally to motor assemblies for boats and more particularly to an improved motor assembly partciularly for use with sail boats to provide an auxiliary power source.

Motor assemblies for use with sail boats which combine the advantages of conventional outboard type motors with inboard type motors have been proposed heretofore. Generally, these systems include some type of swingable arrangement to lower a prop from an inboard motor into the Water. When the motor is not is use, the propeller is retracted within the hull of the boat.

Many difficulties have been encountered with the prior art assemblies of this type which undoubtedly accounts for the fact that very few, if any, are presently on the market. More partciularly, the devices as have been proposed are relatively difficult to install. It is generally required that the entire boat be removed from the water and special tools be provided along with skilled installers. Thus, the installation is expensive and time consuming.

In addition to the above, a relatively large opening has had to be made in the bottom of the hull. As a consequence, leak probles develop and relatively large discontinuities are presented to water flow across the bottom opening. A large opening is generally required because the propller itself must be accommodated when the structure is retracted within the boat and heretofore it has been thought necessary to provide an opening having a width dimension at least corresponding to the diameter of the propeller.

Presently known swingable or retractable type devices generally position a propeller in the water such that its thrust axis has an upward component when the motor is in operation. As a consequence, the rear or stern portion of the boat tends to lift out of the water, and in choppy seas, the entire propeller itself may rise above the waterline and spoin freely with the disadvantage of the engine racing.

There is also the problem in mounting any permanent tyne of motor in a boat in providing an opening for the exhaust. Normally, the opening must be cut in the hull requiring further operations when installing the motor.

Bearing all of the foregoing in mind, it is a primary object of this invention to provide a vastly improved motor assembly particularly useful for sail boats in which the foregoing problems are overcome.

More particularly, it is an object to provide a motor assembly for a sail boat which is extremely simple to install requiring only a single elongated opening to be formed in the bottom stern portion of the hull, the assembly including novel mounting means which eliminates the use of any type of complicated tools all to the end that a private purchaser may readily install the entire motor himself without having to remove his boat from the water.

Still another important object is to provide a motor assembly which, when in operative position, includes a thrust component in a downward direction to keep the stern portion of the boat down so that the propeller is always submerged even in choppy waters.

Still another important object is to provide a motor assembly in which a normal sized propeller may be employed and yet in which the access opening for retracting the structure may have a width considerably less than the diameter of the propeller.

Another important object is to provide a motor as- "ice sembly so designed that an exhaust line may be incorporated therein and exhaust the gases under water, all to the end that further openings in the hull of the boat are not necessary.

Other important objects of this invention are to provide a motor assembly for sail boats which is light, portable, and most important, approximately only half the expense of equivalent structures heretofore proposed.

Briefly, these and many other objects and advantages of this invention are attained by providing a basic fra-rne support structure adapted to be received within a single elongated slot cut in the bottom hull adjacent the stern portion of the boat slightly forward of the boat transom. Cooperating with this supporting structure is a plate having cutout corresponding to the slot and arranged to sandwich the peripheral edges of the slot with the flange on the supporting structure in such a manner as to secure the supporting structure within the slot. The only major operation in installing the device is thus the cutting of the elongated slot in the hull of the boat, this slot being positioned above the water line between the boat transom and the keel so that it is not necessary to remove the boat from the water to install the assembly.

The support structure carries a motor casing Within the stern portion of the boat. An elongated propeller drive shaft housing, in turn, is pivotally mounted to the casing in such a manner as to swing from the first position wholly within the stem to a second position extending through the support plate and slot. Only a single swinging movement is required to position the propeller under the water line, the direction of thrust having a downward component.

Preferably a two bladed propeller is employed and suitable indicating means visible from within the boat are provided for indicating the orientation of the propeller. With this arrangement, the propeller may be aligned with the slot prior to retracting the mechanism so that the slot may be of minimum dimensions and still accommodate the propeller and drive shaft housing.

A further feature of the invention resides in providing an exhaust line which passes through the same housing as that employed for the propeller drive shaft so that no further openings or holes need be made in the hull of the boat.

A better understanding of the invention will be had by now referring to a preferred embodiment as illustrated in the accompanying drawings, in which:

FIGURE 1 is a fragmentary elevational view of a sail boat incorporating the motor assembly of the invention;

FIGURE 2 is an enlarged perspective view partly exploded of the under stern portion of the boat looking in the direction of the arrow 2 of FIGURE 1 and illustrating portions of the motor assembly mounting;

FIGURE 3 is a view partly in cross-section illustrating the motor assembly after being mounted in the boat and in operative position;

FIGURE 4 is another cross-section taken in the direction of the arrows 44 of FIGURE 3;

FIGURE 5 is a cross-section taken in the direction of the arrows 5-5 of FIGURE 3; and,

FIGURE 6 is a cross-section taken in the direction of the arrows 66 of FIGURE 4.

Referring to FIGURE 1, there is shown a sail boat 10 with an under portion of its stem 11 immediately forward of the transom 12 free of the water line L. A propeller 13 extends from the underportion 11 and has a thrust direction T at an angle with the water level L so as to provide a downward component. The stern portion of the sail boat will therefore be held down even in choppy seas. This feature is important as conventional propeller arrangements usually result in an upward component of thrust which tends to lift the stern portion of the boat out of the water.

Referring to FIGURE 2, details of the mounting for the motor assembly of FIGURE 1 will become clear. As shown, the hull portion 11 is provided with an elongated slot 14. This slot may be cut with a simple hand saber saw and since the hull portion 11 is above the water line, the operation may be carried out while the craft is in the water and it is not necessary to haul the sail boat on to dry land.

A frame 15, preferably of open rectangular shape as shown, includes a laterally extending flange 16 about its lower edges. The flange 16 is arranged to cooperate with a plate 17 provided with a central opening for receiving the frame 15. Suitable bolt holes 18 on the flange 16 and 19 about the margin of the plate 17 are provided for securing the frame portion 15 within the slot 14. Further bolt holes 20 are provided in the side of the frame 15 as shown. In the actual assembly, the frame 15 is initially inserted through the slot 14 with the flange 16 seating against the bottom periphery of the slot. The plate 17 is then lowered over the frame 15 from the top inside of the stern portion of the boat to seat on the inside top surface of the peripheral edge of the slot 14 and thus sandwich the periphery of the slot between the plate 17 and flange 16. Suitable bolts are then passed through the cooperating bolt openings 18 and 19.

The foregoing assembled relationship will be clear by referring to FIGURES 3 and 4 wherein the flange 16 and cooperating plate 17 are shown in position with suitable bolts securing the frame 15 within the slot.

A motor casing 21 is designed to be received in the frame 15 and rigidly secured thereto as by means of the bolt holes 20. A propeller drive shaft housing 22 in turn is pivoted to the motor casing 21 as at 23 for swinging movement from a first position illustrated in FIGURE 3 at the dotted lines in which the drive shaft housing 22 is approximately parallel to the plane of the slot, through a 90 angle to a second position in which the housing 22 extends downwardly generally normal to the plane of the slot.

The propeller 13 is driven through a suitable shaft within the housing 22 by means of a drive pulley 24, a V-belt 25, and a gasoline motor 26 supported in the casing 21. The swinging movement of the shaft housing 22 is manually effected by means of a handle or lever 27 on the far side of the casing 21 as illustrated in FIGURE 3.

As shown in both FIGURES 3 and 4, the upper end 28 of the drive shaft in the housing 22 protrudes from the housing so as to be visible through a plastic window 29 formed in the front portion of the motor casing 21. With this arrangement, it is possible for a person in the boat to observe the top end of the drive shaft 28 and thus determine the orientation of the propeller 13 as will become clearer as the description proceeds. This feature is important in that it enable-s the observer to properly position the propeller 13 so that its two blades are in alignment with the slot when it is desired to retract the housing and propeller to its first dotted line position illustrated in FIGURE 3. By so orienting the propeller, it is possible to make the elongated slot in the bottom hull of the stern portion of the boat considerably narrower than would otherwise be the case.

In accord with a further feature of the invention, the exhaust line for the motor 26 illustrated at 30 in FIGURES 3 and 4 is arranged to pass down through the housing 22 and exit from the lower end of the housing thereby exhausting gases beneath the water when the housing 22 is in its second operative position.

FIGURE illustrates the exit port at 31 for the ex haust line 30. By employing the propeller shaft housing 22 as a means for exhausting gases, the necessity of cutting a further opening in the hull of the craft for the exhaust is avoided.

In FIGURE 5, the arrangement of the drive shaft 28 for the propeller will be evident. As shown, this shaft 28 is coupled to a shaft 32 driven by the pulley such as a pulley 24 by means of bevel gears 33 and 34. The lower end of the shaft, in turn, terminates in a bevel gear 35 meshing with a further bevel gear 36 connected to drive the propeller 13. The pivot axis 23 for swinging movement of the housing 22 is coaxial with the shaft 32 for the pulley drive 24 and thus the housing may be swung about suitable journaling bearings 37 and 38 without necessitating any disconnection between the pulley shaft 32 and the propeller drive shaft 38.

FIGURE 6 illustrates a top view of the upper end of the shaft 28 wherein it will be noted there is provided an orientation arrow 39 indicating the orientation of the propeller blades for the propeller 13.

With the foregoing description in mind, the manner in which the motor assembly is installed and operated will be clear. Initially, as stated, an elongated slot such as indicated at 14 is cut in the stern portion of the sail boat as by means of a saber saw. As a specific example, this slot would be of the order of three inches by eighteen inches. The motor assembly frame structure 15, flange 16, and cooperating plate 17 are contoured in accordance with the particular type of boa-t for which the assembly is purchased so as to conform to the geometry of the underside of the hull 11.

After the slot 14 has been cut, the frame 15 is inserted therein and the plate 17 dropped over the frame from the top side of the craft and the mounting structures secured in place. The motor casing 21 and motor assembly 26 as well as the drive shaft housing 22 are all then lowered as a unit from the top side of the craft through the frame and slot and the motor casing 21 then secured to the frame as by means of the bolt holes 20 as illustrated in FIGURE 3.

The lever "or handle 27 may then be swung from the solid line position illustrated in FIGURE 3 to the dotted line position to retract or swing upwardly the shaft housing 22, the operator making sure that the propeller blades 13 are aligned with the housing 22 and thus the slot. The rear wall of the housing 22 is substantially of the same dimensions as the slot and the portion of the rear wall extending above the pivot axis 23 as illustrated in FIG- URE 4 will serve to close the forward portion of the slot when the housing 22 is retracted so that the bottom of the craft will be relatively smooth and continuous.

It will be evident from the foregoing that the installation of the motor assembly is extremely simple and can be carried out by a private owner relatively quickly and with a minimum of tools.

When it is desired to use the motor, the boat operator will simply swing the lever 27 illustrated in FIGURE 3 from the dotted line position to the solid line position thereby lowering the propeller shaft housing 22 to position the propeller 13 as illustrated in solid lines. As stated heretofore, the direction of thrust of the propeller is such that the downward component will maintain the stern portion of the sail boat low and thus the propeller will remain in the water even in choppy seas.

When retracting the housing, the operator need only observe the orientation of the propeller by looking through the plastic window 29 at the arrow 39 on the upper end of the shaft 28. If the propeller blades do not appear to be aligned properly, the operator simply rotates the pulley 24 as by the starting rope for the motor or by any other suitable means until the propeller blades are in alignment with the slot and housing.

It will be evident that when the unit'is retracted, it is completely free of the water since the slot is above the water line. There are thus no openings or holes below the water line and problems of leaks and the like are wholly avoided. Moreover, problems of electrolysis on motor parts and similar difficulties as have characterized prior art devices are avoided.

Since the motor, once mounted, may be deemed a permanent installation, a self-starter may easily be provided if desired.

From the foregoing description, it will accordingly be clear that the presetnt invention has provided a vastly improved motor assembly particularly useful for sail boats. It will also be evident that all of the objects set forth heretofore are completely satisfied by the assembly of this invention.

While only one particular embodiment of the invention has been set forth and described, changes that fall clearly Within the scope and spirit of this invention will occur to those skilled in the art. The motor assembly for boats is therefore not to be thought of as limited to the one embodiment set forth merely for illustrative purposes.

What is claimed is:

1. A motor assembly for boats comprising, in combination; a supporting base structure having an elongated central opening; means for securing said base structure within an elongated slot in the bottom stern portion of a boat; a motor casing and motor secured to said base structure; an elongated propeller shaft housing pivoted to said motor casing for swinging movement from a first position in which said housing is positioned generally parallel to the plane of said slot Within the stern portion of said boat to a second position in which said housing extends downwardly through said central opening and slot; a propeller coupled to the lower end of the propeller shaft in said housing; and indicating means on the upper end of the propeller shaft visible from within said boat indicating the orientation of said propeller so that the same may be aligned with said slot prior to swinging said housing from said second to said first position.

2. A motor assembly for a sail boat, comprising, in combination: a supporting base structure in the form of an open rectangular frame having a laterally extending flange on its lower edges; a cooperating fastening plate having an elongated generally rectangular central opening for receiving said frame such that said frame is receivable in an elongated slot cut in the bottom stern portion of the hull of sail boat slightly forward of the boat transom and above the water line with said flange seating against the bottom periphery of said slot, said plate being positioned over said frame from the top side of said hull to seat against the top periphery of said slot, said flange and frame including cooperating aligned bolt holes for securing said flange to said plate to sandwich the peripheral edge of said slot and thereby secure said frame to said hull; a motor casing including a motor secured to said frame within the stern of said boat; and an elongated propeller drive shaft housing pivotally mounted to said motor casing for swinging movement through approximately about a transverse axis from a first position generally parallel to and enclosed within the stern of said boat to a second position extending downwardly through said open frame and slot generally normal to the plane of said slot.

3. An assembly according to claim 2, including a propeller at the lower end of said housing having a thrust direction at right angles to the elongated axis of said housing, the plane of said slot forming an angle with the water line such that the direction of thrust of said propeller has a downward component when said propeller drive shaft housing is in its second position.

4. An assembly according to claim 2, including a two bladed propeller coupled to said drive shaft at the lower end of said housing, the upper end of said drive shaft including indicating means visible from within said boat indicating the orientation of said propeller so that the same may be aligned with said slot prior to swinging said housing from said second to said first position.

5. An assembly according to claim 2, including an exhaust line for said motor running down through the interior of said elongated housing and opening out the lower end of said housing.

References Cited UNITED STATES PATENTS 695,717 3/1902 Gardiner -41 1,824,887 9/1931 Harvey 11541 2,119,281 5/1938 Luders.

3,116,710 1/1964 Cass 11541 3,150,631 9/1964 Tillman 115-41 X MILTON BUCHLER, Primary Examiner.

T. MAJOR, Assistant Examiner, 

1. A MOTOR ASSEMBLY FOR BOATS COMPRISING, IN COMBINATION; A SUPPORTING BASE STRUCTURE HAVING AN ELONGATED CENTRAL OPENING; MEANS FOR SECURING SAID BASE STRUCTURE WITHIN AN ELONGATED SLOT IN THE BOTTOM STERN PORTION OF A BOAT; A MOTOR CASING AND MOTOR SECURED TO SAID BASE STRUCTURE; AN ELONGATED PROPELLER SHAFT HOUSING PIVOTED TO SAID MOTOR CASING FOR SWINGING MOVEMENT FROM A FIRST POSITION IN WHICH SAID HOUSING IS POSITIONED GENERALLY PARALLEL TO THE PLANE OF SAID SLOT WITHIN THE STERN PORTION OF SAID BOAT TO A SECOND POSITION IN WHICH SAID HOUSING EXTENDS DOWNWARDLY THROUGH SAID CENTRAL OPENING AND SLOT; A PROPELLER COUPLED TO THE LOWER END OF THE PROPELLER 